Frostbite: First aid

Frostbite is when skin and underlying tissues freeze after being exposed to very cold temperatures. The areas most likely to be affected are the fingers, toes, ears, cheeks and chin.

Early signs of frostbite are a numb, pale patch of skin, or skin that feels hard or looks waxy.

You can treat mild frostbite (frostnip) with first aid. All other frostbite requires medical attention. First-aid steps for frostbite are as follows:

Check for hypothermia. Get emergency medical help if you suspect hypothermia. Signs and symptoms of hypothermia include intense shivering, drowsiness and muscle weakness, dizziness, and nausea.

Protect your skin from further damage. If there's any chance the affected areas will freeze again, don't thaw them. If they're already thawed, wrap them up so that they don't refreeze.

If you're outside, warm frostbitten hands by tucking them into your armpits. Protect your face, nose or ears by covering the area with dry, gloved hands. Don't rub the affected area and don't walk on frostbitten feet or toes if possible.

Get out of the cold. Once you're indoors, remove wet clothes and wrap up in a warm blanket. Take care to not break any blisters.

Gently rewarm frostbitten areas. Soak the frostbitten areas in warm water — 99 to 104 F (37 to 40 C). If a thermometer isn't available, test the water by placing an uninjured hand or elbow in it — it should feel very warm — not hot. Rewarming takes about 30 minutes. Stop the soaking when the skin becomes its normal color or loses its numbness.

Don't rewarm frostbitten skin with direct heat, such as a stove, heat lamp, fireplace or heating pad. This can cause burns.

Drink warm liquids. Tea, coffee or soup can help warm you from the inside. Don't drink alcohol.

Know what to expect as skin thaws. If the skin turns red and you feel tingling and burning as it warms, normal blood flow is returning. Seek emergency help if numbness or pain persists during warming, or if you develop blisters.